Adaptive streaming of an immersive video scene

ABSTRACT

Client configured for retrieving a video data representation of an immersive video scene streamed by a server using a streaming protocol, wherein the server is configured for providing a plurality of streams to the client, wherein each of the streams comprises a portion of the immersive video scene, the client comprising: a sending interface; a reception interface; a viewing direction receiving unit; and a stream selecting unit; wherein the sending interface is configured for transmitting a streaming request for streaming the one or more selected streams as the video data representation of the immersive video scene, wherein the sending interface receives from the stream selecting unit a selected stream information identifying the one or more selected streams, wherein the selected stream information is created by the stream selecting unit based on the viewing direction of the user of the client and based on the manifest.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.62/279,810 titled “Adaptive Immersive Streaming of 360° and VirtualReality Video and Environments” and filed Jan. 17, 2016, which isincorporated by reference herein in its entirety.

DESCRIPTION

The present application is concerned with streaming of video scenes.

Media streaming technology allows people to watch a video scene via aclient operating on a person's desktop, mobile phone, computer or thelike.

In particular, the present application is concerned with streaming ofimmersive video scenes. Immersive videos scenes are video recordingswhere a field of view is recorded at the same time, which is larger thana field of view of a user. During playback the user may control hisviewing direction so that he can immerse himself into the video scene.

Although gaming and entertainment are what come to most people's mindswhen discussing immersive video technology, the inevitable reach ofimmersive video technology extends far beyond. Completely novelscenarios, such as virtual workspaces or illustrations in context ofengineering and manufacturing, are within reach in the very near future.However, all of these applications do share one big difficulty—the needto get huge amounts of data to display the video information of anentire sphere. In many cases immersive video scenarios provide a full360° reflection of the real (or an artificial) world, which needsincomparable higher resolutions in contrast to traditional video, if thesame quality level is to be maintained. If one thinks of progressivedownload, or traditional—non adaptive—video streaming, in this context,very high bandwidth connections will be needed to ensure low startupdelay and no buffering. Otherwise the quality of experience for theend-user decreases dramatically.

To overcome this issue and ensure highest video quality, with minimalstartup time and no buffering, adaptive streaming technologies likeMPEG-DASH, Apple HLS, Adobe HDS, Microsoft Smooth Streaming or othersare a perfect fit, and have the potential to enable seamless streamingof immersive video content. This video streaming technique allows thevideo player on the client device to dynamically adapt the video bitrate(quality) to the bandwidth situation of the user. Thus, the video startsfaster, buffering during the streaming session is prevented, and ahigher quality viewing experience is delivered.

The concept of adaptive bitrate streaming may be described as follows:The video content is available in multiple quality versions, which arealso divided in segments of a given amount of time, e.g. 4 seconds. Thissegmentation in the time dimension as well as the quality dimensionempowers the client to decide based on the current bandwidth situation,device context and other information which quality version will bedownloaded at the given time. Due to this approach, the immersive videocontent is streamed using adaptive streaming, thus the video can adaptto the bandwidth condition of the client device.

Compared to prior art in which the immersive video content gets streamedas one single video quality containing all information and viewableareas of the spherical picture, the adaptive streaming of the content isalready a big improvement.

However, the enormous bandwidth consumption of streamed immersive videocontent is still an issue.

Accordingly, it is an object of the present invention to provide aconcept for media streaming which is more efficient in terms of, forexample, transmission bandwidth consumption.

In one aspect the invention provides a client configured for retrievinga video data representation of an immersive video scene streamed by aserver using a streaming protocol, wherein the server is configured forproviding a plurality of streams to the client, wherein each of thestreams comprises a portion of the immersive video scene, the clientcomprising:

a sending interface configured for sending requests concerning theimmersive media scene to the server;

a reception interface configured for receiving the video datarepresentation of the immersive media scene streamed by the server;

a viewing direction receiving unit configured for receiving a viewingdirection of a user of the client, wherein the viewing directionindicates a field of view of the user; and

a stream selecting unit configured for determining one or more selectedstreams of the plurality of streams;

wherein the sending interface is configured for transmitting to theserver a transmitting request for transmitting a manifest, whichcontains for each of the streams of the immersive video scene a portioninformation, which describes properties of the portion of the sphericalimmersive video scene comprised in the respective stream;

wherein the reception interface is configured for receiving the manifestfrom the server; and

wherein the sending interface is configured for transmitting a streamingrequest for streaming the one or more selected streams as the video datarepresentation of the immersive video scene, wherein the sendinginterface receives from the stream selecting unit a selected streaminformation identifying the one or more selected streams, wherein theselected stream information is created by the stream selecting unitbased on the viewing direction of the user of the client and based onthe manifest.

The basic idea of the invention is not to deliver the whole immersivevideo scene at the same time in a single stream. Instead, the immersivevideo scene is split up into portions, wherein the portions arecontained in separate streams. The client is configured in such way,that only those streams are requested from the server which arenecessary to provide that portions of the immersive video scene whichare in the current field of view of the user. Streams containingportions outside of the field of view of the user may be excluded fromstreaming so that the bitrate consumption for streaming the immersivevideo scene may be reduced dramatically.

In another aspect the invention provides a server for streaming a videodata representation of an immersive video scene to a client, the servercomprising:

a receiving interface configured for receiving requests concerning theimmersive video scene from the client; and

a transmitting interface having access to a plurality of streams,wherein each of the streams comprises a portion of the immersive videoscene;

wherein the transmitting interface has access to a manifest, whichcontains for each of the streams of the immersive video scene a portioninformation, which describes properties of the portion of the immersivevideo scene comprised in the respective stream;

wherein the transmitting interface is configured for transmitting themanifest to the client in case that a transmitting request fortransmitting the manifest from the client is received by the receivinginterface;

wherein the receiving interface is configured for receiving from theclient a streaming request for streaming one or more selected streams ofthe plurality of streams, wherein the one or more selected streams aredetermined by the client based on a viewing direction of the user of theclient and based on the manifest; and wherein the transmitting interfaceis configured for streaming the one or more selected streams accordingto the transmitting request as the video data representation of theimmersive video scene to the client using a streaming protocol in casethat the streaming request from the client is received by the receivinginterface.

The server according to the invention provides on request a manifest tothe client, which contains for each of the streams of the immersivevideo scene a portion information, which describes properties of theportion of the immersive video scene comprised in the respective stream.Based on the portion information in the manifest the client may thendetermine those streams, which are needed to be streamed dependent onthe current field of view of the user. The server then may provide thestreams needed, whereas the other streams will not be streamed so thatthe bitrate consumption may be significantly reduced.

In a further aspect the invention provides a method for retrieving, by aclient, a video data representation of an immersive video scene streamedby a server using a streaming protocol, wherein the server is configuredfor providing a plurality of streams to the client, wherein each of thestreams comprises a portion of the immersive video scene, the methodcomprising the steps:

sending, by a sending device, requests concerning the immersive mediascene to the server;

receiving, by a reception interface, the video data representation ofthe immersive video scene streamed by the server;

receiving, by a viewing direction receiving unit, a viewing direction ofa user of the client, wherein the viewing direction indicates a field ofview of the user; and

determining, by a stream selecting unit, one or more selected streams ofthe plurality of streams;

transmitting, by the sending interface, to the server a transmittingrequest for transmitting a manifest, which contains for each of thestreams of the immersive video scene a portion information, whichdescribes properties of the portion of the immersive video scenecomprised in the respective stream;

receiving the manifest from the server by the reception interface; and

transmitting, by the sending interface, a streaming request forproviding one or more selected streams as the video data representationof the immersive video scene, wherein the sending interface receivesfrom the stream selecting unit a selected stream information identifyingthe one or more selected streams, wherein the selected streaminformation is created by the stream selecting unit based on the viewingdirection of the user of the client and based on the manifest.

In another aspect the invention provides a method for streaming a videodata representation of an immersive video scene from a server to aclient, the method comprising the steps:

receiving, by a receiving interface of the server, requests concerningthe immersive video scene from the client; and

accessing, by a transmitting interface of the server, a plurality ofstreams, wherein each of the streams comprises a portion of theimmersive video scene;

accessing, by the transmitting interface, a manifest, which contains foreach of the streams of the immersive video scene a portion information,which describes properties of the portion of the immersive video scenecomprised in the respective stream;

transmitting, by the transmitting interface, the manifest to the clientin case that a transmitting request for transmitting the manifest fromthe client is received by the receiving interface;

receiving, by the receiving interface, from the client a streamingrequest for providing one or more selected streams of the streams,wherein the one or more selected streams are determined by the clientbased on a viewing direction of the user of the client and based on themanifest; and streaming, by the transmitting interface, the one or moreselected streams as the representation of the immersive video scene tothe client using a streaming protocol in case that the streaming requestfrom the client is received by the receiving interface.

Preferred embodiments of the invention are subsequently discussed withrespect to the accompanying drawings, in which:

FIG. 1 illustrates an embodiment of a client and a server according tothe invention in a schematic view;

FIG. 2 illustrates a structure of a spherical video scene of animmersive video scene;

FIG. 3 illustrates an example for a horizontal adaption of the selectionof the selected streams in a top view in case that the user rotates hisviewing direction horizontally;

FIG. 4 illustrates an example for a vertical adaption of the selectionof the selected streams in a side view in case that the user rotates hisviewing direction vertically;

FIG. 5 illustrates an example of selecting the selected streams in aside view;

FIG. 6 illustrates an example of selecting the selected streams in a topview;

FIG. 7 illustrates a further example for a horizontal adaption of theselection of the selected streams in a top view in case that the userrotates his viewing direction horizontally;

FIG. 8 illustrates an example of selecting the selected streams in aside view;

FIG. 9 illustrates an example of selecting the selected streams in a topview;

FIG. 10 illustrates a further example for a horizontal adaption of theselection of the selected streams in case that the user rotates hisviewing direction horizontally;

FIG. 11 illustrates a further example of selecting the selected streamsin a top view for the case that depth information is available;

FIG. 12 illustrates an example for a manifest; and

FIG. 13 illustrates a further example for a manifest.

Equal or equivalent elements or elements with equal or equivalentfunctionality are denoted in the following description by equal orequivalent reference numerals.

In the following description, a plurality of details is set forth toprovide a more thorough explanation of embodiments of the presentinvention. However, it will be apparent to one skilled in the art thatembodiments of the present invention may be practiced without thesespecific details. In other instances, well-known structures and devicesare shown in block diagram form rather than in detail in order to avoidobscuring embodiments of the present invention. In addition, features ofthe different embodiments described hereinafter may be combined witheach other, unless specifically noted otherwise.

FIG. 1 illustrates an embodiment of a client 1 and a server 2 accordingto the invention in a schematic view.

The client 1 is configured for retrieving a video data representation ofan immersive video scene IVS (see FIG. 2) streamed by a server 2 using astreaming protocol, wherein the server 2 is configured for providing aplurality of streams ST to the client 1, wherein each of the streams STcomprises a portion TI (see FIG. 2) of the immersive video scene IVS,the client 2 comprising:

a sending interface 3 configured for sending requests RTM, SR concerningthe immersive media scene IVS to the server 2;

a reception interface 4 configured for receiving the video datarepresentation of the immersive media scene IVS streamed by the server2;

a viewing direction receiving unit 5 configured for receiving a viewingdirection VD (see FIG. 2) of a user of the client 2, wherein the viewingdirection VD indicates a field of view FV (see FIG. 2) of the user; and

a stream selecting unit 6 configured for determining one or moreselected streams SST of the plurality of streams ST;

wherein the sending interface 3 is configured for transmitting to theserver 2 a transmitting request RTM for transmitting a manifest MA,which contains for each of the streams ST of the immersive video sceneIVS a portion information PI (see FIG. 11), which describes propertiesof the portion of the immersive video scene IVS comprised in therespective stream ST;

wherein the reception interface 4 is configured for receiving themanifest MA from the server 2; and

wherein the sending interface 3 is configured for transmitting astreaming request SR for streaming the one or more selected streams SSTas the video data representation of the immersive video scene IVS,wherein the sending interface 3 receives from the stream selecting unit6 a selected stream information SSI identifying the one or more selectedstreams SST, wherein the selected stream information SSI is created bythe stream selecting unit 6 based on the viewing direction VD of theuser of the client and based on the manifest MA.

The server 2 is configured for streaming a video data representation ofan immersive video scene IVS to a client 1, the server 2 comprising:

a receiving interface 7 configured for receiving requests RTM, SRconcerning the immersive video scene IVS from the client 1; and

a transmitting interface 8 having access to a plurality of streams ST,wherein each of the streams ST comprises a portion TI of the immersivevideo scene IVS;

wherein the transmitting interface 8 has access to a manifest MA, whichcontains for each of the streams ST of the immersive video scene IVS aportion information PI, which describes properties of the portion TI ofthe immersive video scene IVS comprised in the respective stream ST;

wherein the transmitting interface 8 is configured for transmitting themanifest MA to the client one in case that a transmitting request RTMfor transmitting the manifest MA from the client one is received by thereceiving interface 7;

wherein the receiving interface 7 is configured for receiving from theclient 1 a streaming request SR for streaming one or more selectedstreams SST of the plurality of streams ST, wherein the one or moreselected streams SST are determined by the client 1 based on a viewingdirection VD of the user of the client one and based on the manifest MA;and

wherein the transmitting interface 8 is configured for streaming the oneor more selected streams SST according to the transmitting request RTMas the video data representation of the immersive video scene IVS to theclient 1 using a streaming protocol in case that the streaming requestSR from the client 1 is received by the receiving interface 7.

The immersive video scene IVS may comprise a fully spherical immersivescene. A fully spherical immersive scene allows the user to rotate hisviewing direction VD horizontally in an azimuth range of from 0° to 360°and vertically in an elevation range from −90° to +90°. However, theimmersive video scene IVS may be limited to a part of a fully sphericalimmersive scene. Such a partial spherical immersive scene allows theuser to rotate his viewing direction VD to a lower extent than a fullyspherical immersive scene.

For producing the immersive video scene IVS, a panorama camera or acollection of cameras may be used, so that the immersive video scene IVSis a representation of a real world scene. However, the immersive videoscene IVS may also be produced using computer technologies that usesoftware to generate the immersive video scene IVS which replicates areal environment or create an imaginary setting. Such artificiallycreated immersive video scenes IVS are often referred to as virtualreality video scenes. Moreover, the immersive video scene IVS may be acombination of real world elements and virtual reality elements, whichis often referred to as augmented reality video scene.

As streaming protocol dynamic adaptive streaming over HTTP may be used.Dynamic adaptive streaming over HTTP (DASH) is an adaptive bitratestreaming technique for high quality streaming of multimedia contentincluding immersive video content over the internet. Dynamic adaptivestreaming over HTTP streaming typically partitions media content into asequence of small temporal segments with each such temporal segmentcontaining a portion of the media content in a short interval ofplayback time. Typically, the content is made available with a mediapresentation description (MPD) file or manifest MA which describesinformation concerning the temporal segments such as timing, URL, mediacharacteristics such as video resolution and bitrates and so forth.

The client is configured for processing the selected streamssimultaneously and for combining at least some of the selected streamsin order to produce a total view of the immersive video scene which thenmay be displayed on a display.

The server is configured for providing the selected streamssimultaneously.

In another aspect the invention provides a system for streaming a videodata representation of an immersive video scene IVS from a server 2 to aclient 1, wherein the server 2 is configured according to the invention,and wherein the client 1 is configured according to the invention.

In a further aspect the invention provides a method for retrieving, by aclient 1, a video data representation of an immersive video scene IVSstreamed by a server 2 using a streaming protocol, wherein the server 2is configured for providing a plurality of streams ST to the client 1,wherein each of the streams ST comprises a portion TI of the immersivevideo scene IVS, the method comprising the steps:

sending, by a sending device 3, requests RTM, SR concerning theimmersive media scene IVS to the server 2;

receiving, by a reception interface 4, the video data representation ofthe immersive video scene IVS streamed by the server;

receiving, by a viewing direction receiving unit 5, a viewing directionVD of a user of the client 1, wherein the viewing direction VD indicatesa field of view FW of the user; and

determining, by a stream selecting unit 6, one or more selected streamsSST of the plurality of streams ST;

transmitting, by the sending interface 3, to the server 2 a transmittingrequest RTM for transmitting a manifest MA, which contains for each ofthe streams ST of the immersive video scene IVS a portion informationPI, which describes properties of the portion TI of the immersive videoscene IVS comprised in the respective stream ST;

receiving the manifest MA from the server to by the reception interface4; and

transmitting, by the sending interface 3, a streaming request SR forproviding the one or more selected streams SST as the video datarepresentation of the immersive video scene IVS, wherein the sendinginterface 3 receives from the stream selecting unit 6 a selected streaminformation SSI identifying the one or more selected streams SST,wherein the selected stream information SSI is created by the streamselecting unit 6 based on the viewing direction VD of the user of theclient 1 and based on the manifest MA.

In another aspect the invention provides a computer program for, whenrunning on a processor, executing the method for retrieving, by a client1, a video data representation of an immersive video scene IVS streamedby a server 2 using a streaming protocol.

In another aspect the invention provides a method for streaming a videodata representation of an immersive video scene IVS from a server 2 to aclient 1, the method comprising the steps:

receiving, by a receiving interface 7 of the server 2, requests RTM, SRconcerning the immersive video scene IVS from the client 1; and

accessing, by a transmitting interface 8 of the server, a plurality ofstreams ST, wherein each of the streams ST comprises a portion TI of theimmersive video scene IVS;

accessing, by the transmitting interface 8, a manifest MA, whichcontains for each of the streams ST of the immersive video scene IVS aportion information PI, which describes properties of the portion TI ofthe immersive video scene IVS comprised in the respective stream ST;

transmitting, by the transmitting interface, the manifest MA to theclient 1 in case that a transmitting request RTM for transmitting themanifest MA from the client 1 is received by the receiving interface;

receiving, by the receiving interface 7, from the client 1 a streamingrequest SR for providing one or more selected streams SST of the streamsST, wherein the one or more selected streams SST are determined by theclient 1 based on a viewing direction VD of the user of the client 1 andbased on the manifest MA; and

streaming, by the transmitting interface 8, the one or more selectedstreams SST as the representation of the immersive video scene IVS tothe client 1 using a streaming protocol in case that the streamingrequest SR from the client is received by the receiving interface 7

In another aspect the invention provides a computer program for, whenrunning on a processor, executing the method for streaming a video datarepresentation of an immersive video scene IVS from a server 2 to aclient 1.

FIG. 2 illustrates a structure of a spherical video scene SVS of animmersive video scene IVS in a two-dimensional representation. As anexample, the immersive video scene IVS comprises one spherical videoscene SVS. The spherical video scene SVS is a fully spherical videoscene, which allows the user to rotate his viewing direction VDhorizontally in an azimuth range of from 0° to 360° and vertically in anelevation range from −90° to +90°. The spherical video scene SVScorresponds to a position of the user (see FIG. 3), which is usually thecenter point of a sphere to which the content is projected to. Thespherical video scene SVS is split up into a plurality of tiles TI,wherein each of the tiles TI represents a regional portion of thespherical video scene SVS. Each of the tiles TI may be streamed in onestream ST of the plurality of streams ST. In the example of FIG. 2 thetiles TI of the plurality of tiles TI are separated horizontally andvertically.

FIG. 3 illustrates an example for a horizontal adaption of the selectionof the selected streams SST in a top view in case that the user rotateshis viewing direction horizontally.

In some embodiments of the client 2 the immersive video scene IVScomprises at least one spherical video scene SVS corresponding to aposition PO of the user of the client 1, wherein the spherical videoscene SVS is split up into a plurality of tiles TI, wherein each of thetiles TI represents a regional portion of the spherical video scene SVS,wherein each of the tiles TI is contained in one stream ST of theplurality of streams ST, wherein for each of the streams ST comprisingone of the tiles TI, the properties described in the portion informationPI (see FIG. 11) comprise a regional description RD (see FIG. 11) of theregional portion represented by the respective tile TI, wherein at leastsome tiles TI of the plurality of tiles TI are separated horizontallyand/or vertically,

wherein the stream selecting unit 6 is configured

for including into the one or more selected streams SST a first groupGS1 of streams ST of the plurality of streams ST, which comprise the oneor more streams ST containing one of the tiles TI, which are at leastpartially inside of the field of view FV of the user, and

for not including into the one or more selected streams SST a secondgroup of the streams, which comprise at least some of the one or morestreams ST containing one of the tiles TI, which are outside of thefield of view FV of the user.

In some embodiments the spherical video scene SVS is split uphorizontally. For this, the spherical video scene SVS is split up intohorizontally separated tiles TI on the side of the server 2, whereineach tile TI is representing an azimuth range of the spherical videoscene SVS. When the user looks in a given azimuthal viewing direction VDthe selected streams SST are selected, requested and downloaded, whenthe user looks in a different azimuthal viewing direction VD—e.g. byturning his head (using a virtual reality headset), by moving the mobiledevice (e.g. smartphone) or by moving the mouse in a web browserenvironment, etc.—different selected streams SST are determined,requested and downloaded.

E.g. if the user turns left, the missing parts of the spherical videoscene SVS on the left side of the currently seen spherical video sceneSVS, which are now seen by the user, are downloaded and the previouslydownloaded parts of the spherical video scene SVS on the right side,which are not seen anymore, are not downloaded any more

FIG. 4 illustrates an example for a vertical adaption of the selectionof the streams SST in a side view in case that the user rotates hisviewing direction vertically.

In some embodiments the spherical video scene SVS is split upvertically. For this, the spherical video scene SVS is split up intovertically separated tiles TI on the side of the server 2. As shown inFIG. 2, the spherical video scene SVS may be split up into verticallyand horizontally separated tiles TI. The respective streams are providedseparately, and the client can download the streams which fit to thecurrent viewing direction of the user.

When the user looks in a given elevational viewing direction VD theselected streams SST are selected, requested and downloaded, when theuser looks in a different elevational viewing direction VD—e.g. byturning his head (using a virtual reality headset), by moving the mobiledevice (e.g. smartphone) or by moving the mouse in a web browserenvironment, etc.—different selected streams SST are selected, requestedand downloaded.

E.g. if the user turns more upwards, the missing parts of the sphericalvideo scene SVS on the upper side of the currently seen spherical videoscene SVS, which are now seen by the user, are downloaded and thepreviously downloaded parts of the spherical video scene SVS the lowerside, which are not seen anymore, are not downloaded any more.

As a result the client 1 decides which combination of portions of thewhole immersive video scene IVS will be downloaded based on the givenviewing direction VD of the user.

FIG. 5 illustrates an example of selecting the selected streams SST in aside view, wherein the quality is adapted in accordance with anelevation angle of the viewing direction VD.

In some embodiments the server 2 is configured for providing at leastone of the plurality of streams ST at different qualities, wherein foreach of the streams ST the properties described in the portioninformation PI comprise a quality description QD (see FIG. 11) of thedifferent qualities being available, wherein the stream selecting unit 6is configured for determining the quality for the at least one stream STbeing available at different qualities based on the viewing direction VDof the user of the client 1 and based on the manifest MA.

The parts of the immersive video scene IVS that are not seen by the userat a given moment may be downloaded in a lower quality, which ispossible using the adaptive streaming approach (as also for the previousmethods). By doing so, the user can turn to any part of the immersivevideo scene IVS and immediately see this parts. However, the bitrateconsumption may be significantly reduced.

In some embodiments the immersive video scene IVS comprises at least onespherical video scene SVS corresponding to a position PO of the user ofthe client 1, wherein the spherical video scene SVS is split up into aplurality of tiles TI, wherein each of the tiles TI represents aregional portion of the spherical video scene SVS, wherein each of thetiles TI is contained in one stream ST of the plurality of streams ST,wherein for each of the streams ST comprising one of the tiles TI, theproperties described in the portion information PI comprise a regionaldescription RD of the regional portion represented by the respectivetile TI, wherein at least some tiles TI of the plurality of tiles TI areseparated horizontally and/or vertically,

wherein the stream selecting unit 6 is configured for including into theone or more selected streams SST a first group GS1 of streams ST of theplurality of streams ST, which comprise the one or more streams STcontaining one of the tiles TI, which are at least partially inside ofthe field of view FV of the user, and a third group GS3 of the streamsST, which comprise at least some of the one or more streams STcontaining one of the tiles TI, which are outside of the field of viewFV of the user,

wherein the stream selecting unit 6 is configured for determining thequality for the first group GS1 of streams ST and the quality for thethird group GS3 of streams ST in such way that the quality of the firstgroup GS1 of streams ST is higher than the quality of the third groupGS3 of streams ST.

FIG. 6 illustrates an example of selecting the selected streams SST in atop view, wherein the quality is adapted in accordance with an azimuthof the viewing direction VD.

In the examples of FIGS. 5 and 6 the parts of the immersive video sceneIVS that are not seen by the user at a given moment may be downloaded ina lower quality, which is possible using the adaptive streaming approach(as also for the previous methods). By doing so, the user can turn toany portion of the immersive video scene IVS and immediately see thisportion. However, the bitrate consumption may be significantly reduced.

FIG. 7 illustrates a further example for a horizontal adaption of theselection of the selected streams SST in a top view in case that theuser rotates his viewing direction VD horizontally.

When the user turns to a different portion of the immersive video sceneIVS, the different portion is in a lower quality than the previousportion. The client 1 recognizes the different field of view FV, reducesthe quality of the portions, which are not seen by the user, andincreases the quality of the portions, which are seen by the user.

A vertical adaption of the selection of the selected streams SST may bedone similarly.

FIG. 8 illustrates an example of selecting the selected streams SST in aside view, which is based on the embodiment of FIG. 5, wherein thequality is adapted in accordance with an elevation angle of the viewingdirection VD.

FIG. 9 illustrates an example of selecting the selected streams SST in atop view, which is based on the example of FIG. 6, wherein the qualityis adapted in accordance with an azimuth of the viewing direction VD.

In embodiments of FIGS. 8 and 9, the stream selecting unit 6 isconfigured for

including into the one or more selected streams SST a fourth group GS4of streams ST of the plurality of streams ST, which comprise at leastsome of the one or more streams ST containing one of the tiles TI, whichare outside of the field of view FV of the user and farer away from thefield of view FV than the tiles of the third group GS3 of the streamsST, and

wherein the stream selecting unit 6 is configured for determining thequality for the third group GS3 of streams ST and the quality for thefourth group GS4 of streams ST in such way that the quality of thefourth group GS4 of streams ST is lower than the quality of the thirdgroup GS3 of streams ST.

According to this approach, the portions near to the currently seenportions of the spherical video scene SVS may be downloaded in a lowerquality, wherein the portions in the back of the user may be downloadedin the lowest quality.

FIG. 10 illustrates a further example for a horizontal adaption of theselection of the selected streams in case that the user rotates hisviewing direction horizontally.

When the user turns to a different portion of the spherical video sceneSVS in this environment slightly or slowly, he/she sees a lower qualityversion of the content instead of a ultralow quality version. As soon asthe user turns the head, the client 1 increases the seen portions of thespherical video scene SVS to a better quality, chooses the lower qualityof the areas next to the seen portion of the spherical video scene SVS,and choses the ultralow quality for the portions of the spherical videoscene SVS in the back of the user.

A vertical adaption of the selection of the selected streams SST may bedone similarly.

FIG. 11 illustrates a further example of selecting the selected streamsfor the case that depth information is available.

In some embodiments the immersive video scene IVS comprises a pluralityof spherical video scenes, wherein the spherical video scenes SVS1, SVS5of the plurality of spherical video scenes SVS1, SVS5 correspond topositions PO1, . . . , PO5 of the user of the client 1 in the immersivevideo scene IVS,

wherein each of the plurality of spherical video scenes SVS1, . . . ,SVS5 consists of a set SOS1, . . . , SOS5 of streams ST of the pluralityof the streams ST, wherein for each of the streams ST the propertiesdescribed in the portion information PI comprise a description to whichspherical video scene SVS1, . . . , SVS5 of the spherical video scenesSVS1, . . . , SVS5 the respective stream ST belongs,

wherein the stream selecting unit 6 is configured for including into theone or more selected streams SST at least one stream ST1 from a firstset SOS1 of the sets SOS1, SOS5 of streams ST, which corresponds to anactual first position PO1 of the positions PO1, . . . , PO5, and atleast one stream ST2 from a second set SOS2 of the sets SOS1, SOS5 ofstreams ST, which corresponds to a second position PO2 of the positionsPO1, . . . , PO5, which is adjacent to the first position PO1, whereinthe at least one stream ST2 from the second set SOS2 of streams STcorresponds to the at least one stream ST1 from the first set SOS1 ofstreams ST, and

wherein the stream selecting unit 6 is configured for determining thequality for the first set SOS1 of streams ST and the quality for thesecond set SOS2 of streams ST in such way that the at least one streamST1 of the first set SOS1 of streams ST has a higher quality than the atleast one stream ST2 of the second set SOS2 of streams ST.

Streams ST from different sets SOS of streams ST correspond, if theycontain corresponding portions of the immersive video scene IVS scenefrom different perspectives.

In some embodiments the stream selecting unit 6 is configured forincluding into the one or more selected streams SST at least one streamST3 of a third set SOS3 of the sets SOS1, SOS5 of streams ST, whichcorresponds to a third position PO3 of the positions PO1, . . . , PO5,wherein the third position PO3 is at the same side of the first positionPO1 as the second position PO2 and farer away from the first positionPO1 than the second position PO2 is away from the first position PO1,wherein the at least one stream ST3 from the third set SOS3 of streamsST corresponds to the at least one stream ST1 from the first set SOS1 ofstreams ST, and

wherein the stream selecting unit 6 is configured for determining thequality for the second set SOS2 of streams ST and the quality for thethird set SOS3 of streams ST in such way that the at least one streamST3 of the third set SOS3 of streams ST has a lower quality than the atleast one stream ST2 of the second set SOS2 of streams ST.

In some embodiments the stream selecting unit 6 is configured forincluding into the one or more selected streams SST at least one streamST4 of a fourth set SOS4 of the sets SOS1, SOS5 of streams, whichcorresponds to a fourth position PO4 of the positions PO1, . . . , PO5,which is adjacent to the first position PO1 and opposite of the secondposition PO2, wherein the at least one stream ST4 from the fourth setSOS4 of streams ST corresponds to the at least one stream ST1 from thefirst set SOS1 of streams ST, and

wherein the stream selecting unit 6 is configured for determining thequality for the first set SOS1 of streams ST and the quality for thefourth set SOS4 of streams ST in such way that the at least one streamST1 of the first set SOS1 of streams ST has a higher quality than atleast one stream ST4 of the fourth set SOS4 of streams ST.

In some embodiments the stream selecting unit 6 is configured forincluding into the one or more selected streams SST at least one streamST5 of a fifth set SOS5 of the sets SOS1, . . . , SOS5 of streams ST,which corresponds to a fifth position PO5 of the positions PO1, . . . ,PO5, wherein the fifth position is at the same side of the firstposition as the fourth position and farer away from the first positionthan the fourth position is away from the first position, wherein the atleast one stream ST5 from the fifth set SOS5 of streams ST correspondsto the at least one stream ST1 from the first set SOS1 of streams ST,and

wherein the stream selecting unit 6 is configured for determining thequality for the fourth set SOS4 of streams ST and the quality for thefifth set SOS5 of streams ST in such way that the at least one streamST5 of the fifth set SOS5 of streams ST has a lower quality than the atleast one stream ST4 of the fourth set SOS4 of streams ST.

If the immersive video scene IVS also includes depth information wherethe user can go forward or backward in the immersive video scene IVS,the previously mentioned techniques may be extended by additionalstreams ST of the immersive video scene IVS representing the differentdepth perspectives available. This can be applied similar to thepreviously mentioned techniques, also in the different qualities.

To give an example of this, FIG. 11 shows the downloading of additionaldepth streams ST of the immersive video scene IVS, e.g. when the usermoves forward or backward. Again the user sees in this case a lower orultralow quality, depending how fast he/she moves forward or backward,and the client 1 starts to adjust the quality based on the new positionof the user in the immersive video scene IVS.

As a further improvement of this setup, the streams ST for the portionsin the front and the back of the user in low-quality or in ultralowquality, can be extended by additional streams ST for the left, right,above and below area of the current field of view FV. These additionalstreams ST can have a lower quality if desired. Again, if the user movesin this case in the immersive video scene IVS, the quality of thedifferent parts of the virtual reality space are adjusted to the newviewing direction.

FIG. 12 illustrates an example for a manifest MA.

In some embodiments the manifest MA is a media presentation descriptionfor dynamic adaptive streaming over HTTP, wherein for each of thestreams ST the portion information PI is integrated in the mediapresentation in an XML tag.

Dynamic adaptive streaming over HTTP allows providing differentrepresentations having different qualities for the streams ST of themedia content. The qualities may differ in bitrate, resolution or otherfactors. A selection of the quality to be downloaded can be made,typically automatically, based on the manifest MA and with viewingdirection VD over user. Thus, dynamic adaptive streaming over a HTTP isbeneficial for the invention.

Adaptive streaming technologies, like MPEG-DASH, Apple HLS, MicrosoftSmooth Streaming or Adobe HDS, describe the content using a manifestfile MA. These manifest files MA described in the different streams STcan be extended to present the variety of different streams representingthe different portions of the immersive video scene IVS. This can bedone by adding the portion information PI, which describes properties ofthe portion of the spherical immersive video scene IVS comprised in therespective stream ST to the manifest MA, so that the client 1 canidentify which stream ST is belonging to which portion of the immersivevideo scene.

The example MPEG-DASH manifest MA integrates regional description RD aspart of an XML tag, e.g. the Period, AdaptionSet, or Representation. Inthe example of FIG. 12 the manifest MA comprises two portioninformations PI1 and PI2 which comprise regional descriptions RD1 andRD2 respectively. Furthermore, the manifest MA comprises qualitydescriptions QD1 and QD2 contained in the portion informations PI1 andP12.

The regional descriptions RD1 and RD2 of the portion informations PI1and PI2 are respective bit stored in the viewInformation attribute inthe AdaptationSet element. The regional descriptions RD1 and RD2 couldalso be stored in the individual representations or in a separate fileand just linked in the manifest MA. Moreover the viewInformation couldcontain additional information that is needed by the client 1 or anymetadata.

FIG. 13 illustrates a further example for a manifest MA. In the furtherexample the MPEG-DASH manifest MA integrate the regional descriptionsRD1 and RD2 as additional XML tag within, e.g., the Period, AdaptionSet,or Representation. As one can see, there are many possibilities toprovide the additional regional descriptions RD1 and RD2 in the manifestfile MA of an adaptive streaming format.

In some embodiments (not explicitly shown in the Figs.) the immersivevideo scene IVS comprises at least one spherical video scene SVScorresponding to a position PO of the user of the client 1, wherein thespherical video scene SVS is split up into a foreground and abackground, wherein the foreground is contained in a fifth group ofstreams ST of the plurality of streams ST and the background iscontained in a sixth group of streams ST of the plurality of streams ST,wherein for each of the streams ST, the properties described in theportion information PI comprise a description whether the respectivestream ST belongs to the foreground or to the background,

wherein the stream selecting unit 6 is configured for including into theone or more selected streams SST those streams ST of the fifth group ofstreams ST, which are at least partially inside of the field of view FVof the user, are included in the one or more selected streams SST, and

wherein the stream selecting unit 6 is configured for not including intothe one or more selected streams SST those streams ST of the fifth groupof streams ST, which are outside of the field of view FV of the user.

The immersive video scene IVS does not need to be split into regulartiles TI. In case of coding efficiency it can make sense to createcompletely different regions, e.g., the background in the image (bluesky) could be one full tile and the other parts could be separated asshown. Elements of the foreground which are completely outside of thefield of few FV may then be excluded from streaming. However, elementsin the foreground that that are partially in the field of view FV of theuser may be downloaded in higher quality as they are partially in the inthe field of view FV (sky) with this approach.

In some embodiments the immersive video scene IVS comprises at least onespherical video scene SVS corresponding to a position PO of the user ofthe client 1, wherein the spherical video scene SVS is split up into aforeground and a background, wherein the foreground is contained in afifth group of streams ST of the plurality of streams ST and thebackground is contained in a sixth group of streams of the plurality ofstreams ST, wherein for each of the streams ST, the properties describedin the portion information PI comprise a description whether therespective stream ST belongs to the foreground or to the background,

wherein the stream selecting unit 6 is configured for including into theone or more selected streams SST at least one stream ST of the fifthgroup of streams ST and at least one stream ST of the sixth group ofstreams ST, and

wherein the stream selecting unit 6 is configured for determining thequality for the fifth group of streams ST and the quality for sixthgroup of streams ST in such way at least one stream ST of the sixthgroup of streams ST has a lower quality than at least one stream of thefifth group of streams ST.

This streaming approach could be further optimized by not downloadingeverything in high quality that is in the field of view FD of the user.The adaptation could be more fine granular for example elements in theforeground could be downloaded in higher quality and the backgroundcould be downloaded in lower quality, this further increases streamingperformance (like object based coding).

Having depth information available could be used to identify objects orobject areas and transferring this objects as separate stream. Thiscould be done according to reference [1]. This means not splitting thevideo into regular shaped tiles TI, e. g. rectangles, rather splittingit into objects. If the user wants to go forward or backward, the o himhim bject could be adapted accordingly. In case of artificialenvironments one would have exact information about objects and thisapproach could be further optimized.

Thus, in some embodiments at least one stream of the fifth group ofstreams may consist of a parametrically coded object.

In some embodiments the immersive video scene IVS is structured intoperiods, wherein the sending interface 3 is configured for transmittingto the server 2 the transmitting request RTM for transmitting themanifest MA for each period of the periods.

The MPEG-DASH concept of periods would also allow to modify the portionsetup/structure (for example the setup of tiles TI and objects) ifneeded e.g., scene cut to something that is completely different.However, the portion setup/structure may also be constant over time.

Depending on certain implementation requirements, embodiments of theinventive device and system can be implemented in hardware and/or insoftware. The implementation can be performed using a digital storagemedium, for example a floppy disk, a DVD, a Blu-ray Disc, a CD, a ROM, aPROM, an EPROM, an EEPROM or a FLASH memory, having electronicallyreadable control signals stored thereon, which cooperate (or are capableof cooperating) with a programmable computer system such that one ormore or all of the functionalities of the inventive device or system isperformed.

In some embodiments, a programmable logic device (for example a fieldprogrammable gate array) may be used to perform one or more or all ofthe functionalities of the devices and systems described herein. In someembodiments, a field programmable gate array may cooperate with amicroprocessor in order to perform one or more or all of thefunctionalities of the devices and systems described herein.

Although some aspects have been described in the context of anapparatus, it is clear that these aspects also represent a descriptionof the corresponding method, where a block or device corresponds to amethod step or a feature of a method step. Analogously, aspectsdescribed in the context of a method step also represent a descriptionof a corresponding block or item or feature of a correspondingapparatus.

Depending on certain implementation requirements, embodiments of theinventive method can be implemented using an apparatus comprisinghardware and/or software. The implementation can be performed using adigital storage medium, for example a floppy disk, a DVD, a Blu-rayDisc, a CD, a ROM, a PROM, an EPROM, an EEPROM or a FLASH memory, havingelectronically readable control signals stored thereon, which cooperate(or are capable of cooperating) with a programmable computer system suchthat the respective method is performed.

Depending on certain implementation requirements, embodiments of theinventive method can be implemented using an apparatus comprisinghardware and/or software.

Some or all of the method steps may be executed by (or using) a hardwareapparatus, like a microprocessor, a programmable computer or anelectronic circuit. Some one or more of the most important method stepsmay be executed by such an apparatus.

Some embodiments according to the invention comprise a data carrierhaving electronically readable control signals, which are capable ofcooperating with a programmable computer system such that one of themethods described herein is performed.

Generally, embodiments of the present invention can be implemented as acomputer program product with a program code, the program code beingoperative for performing one of the methods when the computer programproduct runs on a computer. The program code may for example be storedon a machine readable carrier.

Other embodiments comprise the computer program for performing one ofthe methods described herein, which is stored on a machine readablecarrier or a non-transitory storage medium.

A further embodiment comprises a processing means, for example acomputer, or a programmable logic device, in particular a processorcomprising hardware, configured or adapted to perform one of the methodsdescribed herein.

A further embodiment comprises a computer having installed thereon thecomputer program for performing one of the methods described herein.

Generally, the methods are advantageously performed by any apparatuscomprising hardware and or software.

While this invention has been described in terms of several embodiments,there are alterations, permutations, and equivalents which fall withinthe scope of this invention. It should also be noted that there are manyalternative ways of implementing the methods and compositions of thepresent invention. It is therefore intended that the following appendedclaims be interpreted as including all such alterations, permutationsand equivalents as fall within the true spirit and scope of the presentinvention.

REFERENCE SIGNS

-   1 client-   2 server-   3 sending interface-   4 reception interface-   5 viewing direction receiving unit-   6 stream selecting unit-   7 receiving interface-   8 transmitting interface-   IVS immersive video scene-   ST stream-   TI tile-   SR streaming request-   RTM transmitting request-   VD viewing direction-   FV field of view-   SST selected stream-   MA manifest-   PI portion information-   SSI selected stream information-   SVS spherical video scene-   PO position-   RD regional description-   GS group of streams-   QD quality description-   SOS set of streams

REFERENCES

-   [1] Fabian Prada, Leandro Cruz, Luiz Velho: Improving Object    Extraction With Depth-Based Methods, online available:    http://www.visgraf.impa.br/Data/RefBib/PS_PDF/clei13/clei2013    81.pdf.

1. Client configured for retrieving a video data representation of animmersive video scene streamed by a server using a streaming protocol,wherein the server is configured for providing a plurality of streams tothe client, wherein each of the streams comprises a portion of theimmersive video scene, the client comprising: a sending interfaceconfigured for sending requests concerning the immersive media scene tothe server; a reception interface configured for receiving the videodata representation of the immersive media scene streamed by the server;a viewing direction receiving unit configured for receiving a viewingdirection of a user of the client, wherein the viewing directionindicates a field of view of the user; and a stream selecting unitconfigured for determining one or more selected streams of the pluralityof streams; wherein the sending interface is configured for transmittingto the server a transmitting request for transmitting a manifest, whichcontains for each of the streams of the immersive video scene a portioninformation, which describes properties of the portion of the sphericalimmersive video scene comprised in the respective stream; wherein thereception interface is configured for receiving the manifest from theserver; and wherein the sending interface is configured for transmittinga streaming request for streaming the one or more selected streams asthe video data representation of the immersive video scene, wherein thesending interface receives from the stream selecting unit a selectedstream information identifying the one or more selected streams, whereinthe selected stream information is created by the stream selecting unitbased on the viewing direction of the user of the client and based onthe manifest.
 2. Client according to claim 1, wherein the immersivevideo scene comprises at least one spherical video scene correspondingto a position of the user of the client, wherein the spherical videoscene is split up into a plurality of tiles, wherein each of the tilesrepresents a regional portion of the spherical video scene, wherein eachof the tiles is contained in one stream of the plurality of streams,wherein for each of the streams comprising one of the tiles, theproperties described in the portion information comprise a descriptionof the regional portion represented by the respective tile, wherein atleast some tiles of the plurality of tiles are separated horizontallyand/or vertically, wherein the stream selecting unit is configured forincluding into the one or more selected streams a first group of streamsof the plurality of streams, which comprise the one or more streamscontaining one of the tiles, which are at least partially inside of thefield of view of the user, and for not including into the one or moreselected streams a second group of the streams, which comprise at leastsome of the one or more streams containing one of the tiles, which areoutside of the field of view of the user.
 3. Client according to claim1, wherein the server is configured for providing at least one of theplurality of streams at different qualities, wherein for each of thestreams the properties described in the portion information comprise aquality description of the different qualities being available, whereinthe stream selecting unit is configured for determining the quality forthe at least one stream being available at different qualities based onthe viewing direction of the user of the client and based on themanifest.
 4. Client according to claim 3, wherein the immersive videoscene comprises at least one spherical video scene corresponding to aposition of the user of the client, wherein the spherical video scene issplit up into a plurality of tiles, wherein each of the tiles representsa regional portion of the spherical video scene, wherein each of thetiles is contained in one stream of the plurality of streams, whereinfor each of the streams comprising one of the tiles, the propertiesdescribed in the portion information comprise a description of theregional portion represented by the respective tile, wherein at leastsome tiles of the plurality of tiles are separated horizontally and/orvertically, wherein the stream selecting unit is configured forincluding into the one or more selected streams a first group of streamsof the plurality of streams, which comprise the one or more streamscontaining one of the tiles, which is at least partially inside of thefield of view of the user, and a third group of the streams, whichcomprise at least some of the one or more streams containing one of thetiles, which is outside of the field of view of the user, wherein thestream selecting unit is configured for determining the quality for thefirst group of streams and the quality for the third group of streams insuch way that the quality of the first group of streams is higher thanthe quality of the third group of streams.
 5. Client according to claim4, wherein the stream selecting unit is configured for including intothe one or more selected streams a fourth group of streams of theplurality of streams, which comprise at least some of the one or morestreams containing one of the tiles, which is outside of the field ofview of the user and farer away from the field of view than the tiles ofthe third group of the streams, and wherein the stream selecting unit isconfigured for determining the quality for the third group of streamsand the quality for the fourth group of streams in such way that thequality of the fourth group of streams is lower than the quality of thethird group of streams.
 6. Client according to claim 3, wherein theimmersive video scene comprises a plurality of spherical video scenes,wherein the spherical video scenes of the plurality of spherical videoscenes correspond to positions of the user of the client in theimmersive video scene, wherein each of the plurality of spherical videoscenes consists of a set of streams of the plurality of the streams,wherein for each of the streams the properties described in the portioninformation comprise a description to which spherical video scene of thespherical video scenes the respective stream belongs, wherein the streamselecting unit is configured for including into the one or more selectedstreams at least one stream from a first set of the sets of streams,which corresponds to an actual first position of the positions, and atleast one stream from a second set of the sets of streams, whichcorresponds to a second position of the positions, which is adjacent tothe first position, wherein the at least one stream from the second setof streams corresponds to the at least one stream from the first set ofstreams, and wherein the stream selecting unit is configured fordetermining the quality for the first set of streams and the quality forthe second set of streams in such way that the at least one stream ofthe first set of streams has a higher quality than the at least onestream of the second set of streams.
 7. Client according to claim 6,wherein the stream selecting unit is configured for including into theone or more selected streams at least one stream of a third set of thesets of streams, which corresponds to a third position of the positions,wherein the third position is at the same side of the first position asthe second position and farer away from the first position than thesecond position is away from the first position, wherein the at leastone stream from the third set of streams corresponds to the at least onestream from the first set of streams, and wherein the stream selectingunit is configured for determining the quality for the second set ofstreams and the quality for the third set of streams in such way thatthe at least one stream of the third set of streams has a lower qualitythan the at least one stream of the second set of streams.
 8. Clientaccording to claim 6, wherein the stream selecting unit is configuredfor including into the one or more selected streams at least one streamof a fourth set of the sets of streams, which corresponds to a fourthposition of the positions, which is adjacent to the first position andopposite of the second position, wherein the at least one stream fromthe fourth set of streams corresponds to the at least one stream fromthe first set of streams, and wherein the stream selecting unit isconfigured for determining the quality for the first set of streams andthe quality for the fourth set of streams in such way that the at leastone stream of the first set of streams has a higher quality than atleast one stream of the fourth set of streams.
 9. Client according toclaim 8, wherein the stream selecting unit is configured for includinginto the one or more selected streams at least one stream of a fifth setof the sets of streams, which corresponds to a fifth position of thepositions, wherein the fifth position is at the same side of the firstposition as the fourth position and farer away from the first positionthan the fourth position is away from the first position, wherein the atleast one stream from the fifth set of streams corresponds to the atleast one stream from the first set of streams, and wherein the streamselecting unit is configured for determining the quality for the fourthset of streams and the quality for the fifth set of streams in such waythat the at least one stream of the fifth set of streams has a lowerquality than the at least one stream of the fourth set of streams. 10.Client according to claim 1, wherein the manifest is a mediapresentation description for dynamic adaptive streaming over HTTP,wherein for each of the streams the portion information is integrated inthe media presentation in an XML tag.
 11. Client according to claim 1,wherein the immersive video scene comprises at least one spherical videoscene corresponding to a position of the user of the client, wherein thespherical video scene is split up into a foreground and a background,wherein the foreground is contained in a fifth group of streams of theplurality of streams and the background is contained in a sixth group ofstreams of the plurality of streams, wherein for each of the streams,the properties described in the portion information comprise adescription whether the respective stream belongs to the foreground orto the background, wherein the stream selecting unit is configured forincluding into the one or more selected streams those streams of thefifth group of streams, which are at least partially inside of the fieldof view of the user, are included in the one or more selected streams,and wherein the stream selecting unit is configured for not includinginto the one or more selected streams those streams of the fifth groupof streams, which are outside of the field of view of the user. 12.Client according to claim 3, wherein the immersive video scene comprisesat least one spherical video scene corresponding to a position of theuser of the client, wherein the spherical video scene is split up into aforeground and a background, wherein the foreground is contained in afifth group of streams of the plurality of streams and the background iscontained in a sixth group of streams of the plurality of streams,wherein for each of the streams, the properties described in the portioninformation comprise a description whether the respective stream belongsto the foreground or to the background, wherein the stream selectingunit is configured for including into the one or more selected streamsat least one stream of the fifth group of streams and at least onestream of the sixth group of streams, and wherein the stream selectingunit is configured for determining the quality for the fifth group ofstreams and the quality for sixth group of streams in such way at leastone stream of the sixth group of streams has a lower quality than atleast one stream of the fifth group of streams.
 13. Client according toclaim 12, wherein at least one stream of the fifth group of streamsconsists of a parametrically coded object.
 14. Client according to claim1, wherein the immersive video scene is structured into periods, whereinthe sending interface is configured for transmitting to the server thetransmitting request for transmitting the manifest for each period ofthe periods.
 15. Server for streaming a video data representation of animmersive video scene to a client, the server comprising: a receivinginterface configured for receiving requests concerning the immersivevideo scene from the client; and a transmitting interface having accessto a plurality of streams, wherein each of the streams comprises aportion of the immersive video scene; wherein the transmitting interfacehas access to a manifest, which contains for each of the streams of theimmersive video scene a portion information, which describes propertiesof the portion of the immersive video scene comprised in the respectivestream; wherein the transmitting interface is configured fortransmitting the manifest to the client in case that a transmittingrequest for transmitting the manifest from the client is received by thereceiving interface; wherein the receiving interface is configured forreceiving from the client a streaming request for streaming one or moreselected streams of the plurality of streams, wherein the one or moreselected streams are determined by the client based on a viewingdirection of the user of the client and based on the manifest; andwherein the transmitting interface is configured for streaming the oneor more selected streams according to the transmitting request as thevideo data representation of the immersive video scene to the clientusing a streaming protocol in case that the streaming request from theclient is received by the receiving interface.
 16. System for streaminga video data representation of an immersive video scene from a server toa client, wherein the server is configured according to claim 15, andwherein the client is configured according to claim
 1. 17. Method forretrieving, by a client, a video data representation of an immersivevideo scene streamed by a server using a streaming protocol, wherein theserver is configured for providing a plurality of streams to the client,wherein each of the streams comprises a portion of the immersive videoscene, the method comprising the steps: sending, by a sending device,requests concerning the immersive media scene to the server; receiving,by a reception interface, the video data representation of the immersivevideo scene streamed by the server; receiving, by a viewing directionreceiving unit, a viewing direction of a user of the client, wherein theviewing direction indicates a field of view of the user; anddetermining, by a stream selecting unit, one or more selected streams ofthe plurality of streams; transmitting, by the sending interface, to theserver a transmitting request for transmitting a manifest, whichcontains for each of the streams of the immersive video scene a portioninformation, which describes properties of the portion of the immersivevideo scene comprised in the respective stream; receiving the manifestfrom the server by the reception interface; and transmitting, by thesending interface, a streaming request for providing one or moreselected streams as the video data representation of the immersive videoscene, wherein the sending interface receives from the stream selectingunit a selected stream information identifying the one or more selectedstreams, wherein the selected stream information is created by thestream selecting unit based on the viewing direction of the user of theclient and based on the manifest.
 18. Computer program for, when runningon a processor, executing the method according to claim
 15. 19. Methodfor streaming a video data representation of an immersive video scenefrom a server to a client, the method comprising the steps: receiving,by a receiving interface of the server, requests concerning theimmersive video scene from the client; and accessing, by a transmittinginterface of the server, a plurality of streams, wherein each of thestreams comprises a portion of the immersive video scene; accessing, bythe transmitting interface, a manifest, which contains for each of thestreams of the immersive video scene a portion information, whichdescribes properties of the portion of the immersive video scenecomprised in the respective stream; transmitting, by the transmittinginterface, the manifest to the client in case that a transmittingrequest for transmitting the manifest from the client is received by thereceiving interface; receiving, by the receiving interface, from theclient a streaming request for providing one or more selected streams ofthe streams, wherein the one or more selected streams are determined bythe client based on a viewing direction of the user of the client andbased on the manifest; and streaming, by the transmitting interface, theone or more selected streams as the representation of the immersivevideo scene to the client using a streaming protocol in case that thestreaming request from the client is received by the receivinginterface.
 20. Computer program for, when running on a processor,executing the method according to claim 19.